A novel approach to chemotaxis: active particles guided by internal clocks

TL;DR

This paper introduces a minimal model where active particles use an internal clock influenced by external chemical gradients to navigate, offering a new approach to directional control in active matter systems.

Contribution

It presents a novel phenomenological model demonstrating how internal clocks can enable active particles to detect and respond to external concentration gradients.

Findings

Particles can detect chemical gradients using internal clocks.

Clock design determines movement up- or down-gradient.

Model offers a versatile tool for engineering behavioral responses.

Abstract

Motivated by the observation of non-exponential run-time distributions of bacterial swimmers, we propose a minimal phenomenological model for taxis of active particles whose motion is controlled by an internal clock. The ticking of the clock depends on an external concentration field, e.g. a chemical substance. We demonstrate that these particles can detect concentration gradients and respond to them by moving up- or down-gradient depending on the clock design, albeit measurements of these fields are purely local in space and instantaneous in time. Altogether, our results open a new route in the study of directional navigation, by showing that the use of a clock to control motility actions represents a generic and versatile toolbox to engineer behavioral responses to external cues, such as light, chemical, or temperature gradients.